From 2019, Grand Slams will also revert to 16 seeds from the current 32 - going back to the system that was in place until Wimbledon 2001. That year, both the Australian Open and Roland Garros had seen the No.2 seed pitted against the World No.25 in the first round, with Lindsay Davenport beating Jelena Dokic in three sets in Melbourne and Venus Williams falling to Barbara Schett in Paris.

The 32-seed system has seen little effect on unseeded players progressing to the latter rounds of Slams. Over the 10 Slams preceding the switch to 32, there were 19 unseeded players who reached the quarterfinals or better - the same number as in the last 10 Slams under 32 seeds.

Indeed, the 16-seed system could still lead to an all-seeded quarterfinal lineup (such as the 2001 Australian Open and 1998 US Open). Meanwhile, over the 16 years of the 32-seed system, there have been 18 unseeded semifinalists, two unseeded finalists (Justine Henin at the 2010 Australian Open and Roberta Vinci at the 2015 US Open) and even four unseeded champions (Serena Williams at the 2007 Australian Open, Kim Clijsters at the 2009 US Open, Jelena Ostapenko at Roland Garros in 2017 and Sloane Stephens at the 2017 US Open).